Use timestamp check for token refresh (#1444)

Signed-off-by: Terence Lim <terencelimxp@gmail.com>

sdk/python/feast/grpc/auth.py

@@ -13,6 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import json
+import time
 from http import HTTPStatus
 
 import grpc
@@ -159,6 +160,7 @@ def __init__(self, config: Config):
 
         self._static_token = None
         self._token = None
+        self._token_expiry_ts = time.time()
 
         # If provided, set a static token
         if config.exists(opt.AUTH_TOKEN):
@@ -169,6 +171,9 @@ def __init__(self, config: Config):
 
     def get_signed_meta(self):
         """ Creates a signed authorization metadata token."""
+
+        if time.time() > self._token_expiry_ts:
+            self._refresh_token()
         return (("authorization", "Bearer {}".format(self._token)),)
 
     def _refresh_token(self):
@@ -179,10 +184,13 @@ def _refresh_token(self):
             self._token = self._static_token
             return
 
-        from google.oauth2.id_token import fetch_id_token
+        from google.oauth2.id_token import fetch_id_token, verify_oauth2_token
 
         try:
             self._token = fetch_id_token(self._request, audience="feast.dev")
+            self._token_expiry_ts = verify_oauth2_token(self._token, self._request)[
+                "exp"
+            ]
             return
         except DefaultCredentialsError:
             pass
@@ -195,6 +203,9 @@ def _refresh_token(self):
             credentials.refresh(self._request)
             if hasattr(credentials, "id_token"):
                 self._token = credentials.id_token
+                self._token_expiry_ts = verify_oauth2_token(self._token, self._request)[
+                    "exp"
+                ]
                 return
         except DefaultCredentialsError:
             pass  # Could not determine credentials, skip

sdk/python/tests/grpc/test_auth.py

@@ -147,9 +147,13 @@ def test_get_auth_metadata_plugin_oauth_should_raise_when_config_is_incorrect(
         get_auth_metadata_plugin(config_with_missing_variable)
 
 
+@patch(
+    "google.oauth2.id_token.verify_token",
+    return_value={"iss": "accounts.google.com", "exp": 12341234},
+)
 @patch("google.oauth2.id_token.fetch_id_token", return_value="Some Token")
 def test_get_auth_metadata_plugin_google_should_pass_with_token_from_gcloud_sdk(
-    fetch_id_token, config_google
+    verify_token, fetch_id_token, config_google
 ):
     auth_metadata_plugin = get_auth_metadata_plugin(config_google)
     assert isinstance(auth_metadata_plugin, GoogleOpenIDAuthMetadataPlugin)
@@ -158,6 +162,10 @@ def test_get_auth_metadata_plugin_google_should_pass_with_token_from_gcloud_sdk(
     )
 
 
+@patch(
+    "google.oauth2.id_token.verify_token",
+    return_value={"iss": "accounts.google.com", "exp": 12341234},
+)
 @patch(
     "google.auth.default",
     return_value=[
@@ -167,7 +175,7 @@ def test_get_auth_metadata_plugin_google_should_pass_with_token_from_gcloud_sdk(
 )
 @patch("google.oauth2.id_token.fetch_id_token", side_effect=DefaultCredentialsError())
 def test_get_auth_metadata_plugin_google_should_pass_with_token_from_google_auth_lib(
-    fetch_id_token, default, config_google
+    verify_token, fetch_id_token, default, config_google
 ):
     auth_metadata_plugin = get_auth_metadata_plugin(config_google)
     assert isinstance(auth_metadata_plugin, GoogleOpenIDAuthMetadataPlugin)